The present embodiments relate to three-dimensional (3D) reconstruction of the left atrium and pulmonary veins.
Computer tomography (CT) and magnetic resonance imaging (MRI) may be used to obtain images of the human body, such as the left atrium and pulmonary veins. The left atrium is one of the four chambers in the human heart. The left atrium receives oxygenated blood from the pulmonary veins and pumps the blood into the left ventricle. The four pulmonary veins carry oxygen-rich blood from the lungs to the left atrium of the heart. The lungs receive blood from the pulmonary artery.
Computer tomography (CT) and magnetic resonance imaging (MRI) are used to produce images of the left atrium and pulmonary veins. The images may be used to determine the morphology of the left atrium and the number, size and position of the pulmonary veins. This anatomical information is desired, because ablation in the left atrium is mainly performed around the ostia openings of the pulmonary veins.
Several days may pass between the taking of the images and the therapy. During this time, anatomical structures are often displaced. Moreover, the shape and size of the atrium may change during this time.
Two different 3D data sets may be obtained using an X-ray system that is employed for the therapy. The imaging of the 3D data may be performed immediately (directly) prior to or in the course of the therapy. Two different data sets of the left atrium are obtained. The first data set is of one half of the left atrium and pulmonary veins, and the second data set is of the other half of the left atrium and pulmonary veins. The first and second data sets are used to obtain two different 3D representations of the left atrium and pulmonary veins. Obtaining the data sets requires injecting a contrast agent into the patient and applying a radiation dosage for each the first and second data sets. In other words, a contrast agent is injected into the patient twice and the patient is subject to a radiation dosage twice. The two 3D representations are fused together to obtain a single 3D representation of the left atrium and pulmonary veins.
Obtaining the first and second data sets is required because X-ray systems, which are used in electrophysiology and cardiology, are equipped with a small (e.g., 20 cm×20 cm) detector. Because of the size of the detector, it is difficult to obtain a single data set representing the left atrium and pulmonary veins. The size of the detector makes it difficult to position the detector, such that the detector obtains a data set that may be used to generate a 3D representation of the left atrium and all of the pulmonary veins.